OpenGL header file not found
 

Trying to install flightgear on gentoo 1.4.

One of the dependencies is plib. When it atries to compile plib I get:

creating cache ./config.cache
checking for a BSD compatible install... /bin/install -c
checking whether build environment is sane... yes
checking whether make sets ${MAKE}... yes
checking for working aclocal... found
checking for working autoconf... found
checking for working automake... found
checking for working autoheader... found
checking for working makeinfo... found
includedir changed to ${prefix}/include/plib libdir is ${exec_prefix}/lib
checking for gcc... gcc
checking whether the C compiler (gcc -march=i686 -O3 -pipe ) works... yes
checking whether the C compiler (gcc -march=i686 -O3 -pipe ) is a cross-compiler... no
checking whether we are using GNU C... yes
checking whether gcc accepts -g... yes
checking how to run the C preprocessor... gcc -E
checking for c++... g++
checking whether the C++ compiler (g++ -march=i686 -O3 -pipe ) works... yes
checking whether the C++ compiler (g++ -march=i686 -O3 -pipe ) is a cross-compiler... no
checking whether we are using GNU C++... yes
checking whether g++ accepts -g... yes
checking how to run the C++ preprocessor... g++ -E
checking for a BSD compatible install... /bin/install -c
checking for ranlib... ranlib
checking host system type... i686-pc-linux-gnu
checking for X... libraries /usr/X11R6/lib, headers /usr/X11R6/include
checking for dnet_ntoa in -ldnet... no
checking for dnet_ntoa in -ldnet_stub... no
checking for gethostbyname... yes
checking for connect... yes
checking for remove... yes
checking for shmat... yes
checking for IceConnectionNumber in -lICE... yes
checking for glNewList in -lGL... yes
checking for gluLookAt in -lGLU... yes
checking for glutGetModifiers in -lfreeglut... no
checking for glutGetModifiers in -lglut... yes
checking for dlclose in -ldl... yes
checking for ALopenport in -laudio... no
checking for ANSI C header files... yes
checking for windows.h... no
checking for GL/gl.h... no
configure: error: OpenGL header file not found

I've checked and gl.h does exist in usr/X11R6/include.

Any ideas?

Cheers,

Simon

Sorry that should have read, gl.h does exist in /usr/X11R6/include/GL/